Search resumes for man missing in Manukau Harbour

An eight-year-old girl who had to tread water for hours in the Manukau Harbour after her father went missing on a fishing trip has been interviewed by police.

Police say it's unlikely the 52-year-old has survived after their 4-metre aluminium runabout was found adrift on Wednesday night with no one on board.

Volunteers searched into the night for the missing man along with Westpac Rescue Helicopter, the Police Eagle Helicopter and the Airport Emergency Service Hovercraft.

A search for the dad by water and air resumed on Thursday morning, but Senior Constable Kevin Stone says the man has likely died.

The boat has since been found and will be recovered on Thursday afternoon.

His daughter spent more than two hours in Manukau Harbour before begin plucked exhausted from the water by rescuers.

The emergency call came at 5:07pm on Wednesday when the pair's dinghy was found empty in the Papakura Channel.

Coastguard volunteers in four boats then began searching.

The eight-year-old was discovered at 7:22pm when a rescuer heard her crying out. She had separated from her father more than an hour earlier.

She was taken to Middlemore Hospital but has since been released to family.

"She was recovered from the water by Coastguard volunteers, cold, exhausted, slightly confused but otherwise unharmed. She was then transferred by the Airport Hovercraft who transported her to an awaiting ambulance at nearby Auckland Airport," the Coastguard said.

She's now been interviewed by police who are still trying to confirm if the pair were wearing lifejackets. Early inquiries haven't yet been able to figure out what went wrong.